A union-hired witness didn’t show much compassion for commuters as he told a board looking into railroad pay raises that passengers were actually riding the gravy train, according to new testimony that was revealed Wednesday.

“The passengers have had a good run at the MTA, and it is about time the fare went up,” testified expert witness Tom Roth at a hearing of a committee appointed by President Obama to look into wage increases for LIRR workers.

The cavalier pro-union comment was revealed as the MTA Wednesday announced it was rejecting the panel’s recommendation to raise pay. Last month, the panel had called for a 2.83 percent hike.

The next step is a 60-day cooling-off period, after which each side can seek a different presidential board to look at the issue, a source said.

The recommendations, if enacted, would have “dramatic negative consequences that would affect the entire New York metropolitan area, the most transit dependent region in the United States,” the MTA labor relations director Anita Miller said.

Despite Roth’s claims, LIRR riders were hit last year with their sixth fare hike since 2003.